Electric accumulator



2 SHEETS Patented May l@ UMULATOR.

G. IVIARCON! ELECTRIC ACC APPLlcAnoN man MAR.9,1918.

G. MARCONI. ELECTRIC ACCUIVIULATOR.

APPLICATION FILED MAR. 9, 19I8. LSTJQQD Patented May W192i.

2 SHEES--SHEET 2.

1 in wavy lines) which PAEN'r trice.

GUGLIELMO MARCONI, 0F LONDUN, ENGLAND.

ELECTRIC ACC'UMULATOR.

Specification of Letters Eatent.

Patented tray io, rear..

application Bled March 9, 1911.8.` Serial No. 221,501.

To all whom t may concern:

Be it known that ll, GUGLIELMO MARCONI, a subject of the King of Italy,residing at Marconi House, Strand, London, England, have invented a newand useful Improvement in Electric Accumulators, of which the followingis a specification.

This invention relates to electricaccumulators in which chlorin isemployed as the active element at the positive pole and zinc or othermetal at the negative pole.

According to this invention l employ a solution of an alkaline chlorid(which eX- pression hereinafter means the chlorid of an alkali or ofanalkaline earth) together with the chlorid of an electropo'sitive metalsuch as zinc.

My invention is illustrated by the accompanying drawings, of whichFigure 1 is a vertical section through an accumulator, Fig. 2 is a parttransverse section to a larger scale, and Fig. 3 is a partvertical-section.

a is a cylindrical container of steel having its interior coated withzinc to a thickness of from 1 to 2 mm. It is closed at the bottom by aninsulated cover b. c, 0, are porous cylinders of asbestos or porcelainclosed at the top; each is surrounded with small gauze cylinders d(shown in Fig. 1

by straight lines `only to avoid confusion of the drawing) of copper oriron wire coated with zinc and amalgamated and the whole assemblage isbound together by al large cylinder all of similar gauze (shown in Fig.fits close against the interior of the container a. In the middle ofeach cylinder c is a rod e of carbon having a metallic core f toincrease its conductivity, theremainder of the interior of the cylinderbeing lled with powdered or granular porous carbon g of low resistance.The cores f are not essential, but if they are employed the carbon rodsshould be rendered impermeable by mixing with the paste of which theyare formed a small quantity of a vitreous substance, such as aninsoluble silicate or quartz. The lower end of each cylinder c is closedby a plug hf of insulating cement unaffected by chlorin.

rllhe ends of the cores f, or of the rods e if cores are not employed,are electrically connected to a disk v1 of wire gauze connected to thecover b by solder y'.

lo is a layer of insulating cement, such as Sealing wax, asphalt or vamixture of b1tumen and pitch, introduced hot through a tube l. Above thetop of the cylinders c is a layer of carbon grains m, grains m bemgseparated from carbon parts e and g by the ends of cylinders c. n is anaqueous solution of calcium chlorid and zinc chlorid which can beintroduced through a cock o. p 1s a pressure gage filled with oil toprevent any corroslve action upon it, and g is a safety valve. lin thecenter of the assemblage of cylinders 0 is a circulating tube' r formedof porcelain, through which passes a closed tube s of metal coated withlzinc and containing a coil the ends of which are connected to bindingscrews t. u is the positive terminal of the accumulator and fu thenegative terminal. One binding screw t is connected to the terminal uand the other tothe terminal v so that a current may dow through thecoil and heat it and so cause a circulation of the solution. After thewhole has been assembled and the solution introduced air orhydrogen isforced into the container to a pressure of the order of twentyatmospheres.

The action of the accumulator is as follows During charging the chloridof zinc is decomposed into chlorin and zinc. The latter is deposited onthe surface of the gauze constituting thevnegative electrode, and thechlorin which is liquefied by the pressure is partly absorbed by thepowdered carbon, while. some remains free in the solution. Duringdischarge the reverse action takes place, the anions of chlorin and thecations of zinc recombining to form chlorid of zinc. rlhe presence ofthe calcium chlorid prevents shortcircuiting being caused owing to thegrowth of laments of zinc through the pores of the cylinders containingthe positive electrodes, and decreases the diffusion of the chlorinthrough the liquid.

'While ll prefer zinc, l may use in place of it another electropositivemetal, such as cadmium, or ossibly nickel, iron, copper or manganese.Iimilarly, while I prefer calcium chlorid as being cheap and extremelysoluble, ll may employ in place of it the chlorid of some other alkalior alkaline earth metal, such as common salt.

Internal diameter of container a 20cm Height 50 cm Number of cylinders c300 Internal diameter of 0 8 mm Thickness of sides of c 1 mm Diameter ofrods e 5 mm Diameter of cores f 1 mm Gauze ci is formed of wire of 0.2mm. diameter of close mesh, weighing approximately 8 gramsper squaredecimeter. l

In place of wire-gauze I may employ perforated strips ofv electrolyticzlnc and the Word gauze taken as including such strips.

The solution should be prepared with distilled Water, and the chloridsof calcium and zinc should be pure and lfree from metals moreelectronegative than zinc.

The solution may consist of:-

600 grams of water.

500 to 550 grams of dry chlorld of calcium, and

400 grams of chlorid of zmc.

For accumulators in which weight and size are not of essentialimportance, 1t 1s possible to 0 diameters of the cylinders c and thethlckness of their sides.

An accumulator so constructed has a capacity of about 1,100 ampere hourswith an initial voltage of from 2te 2.2 volts, the discharge rate beingabout five hours and the voltage drops to 1.6 volts.

What I claim is 1. In an electric accumulator, the combination of aclosed container, electrodes therein, and an electrolyte in saidcontainer containing chlorin ions, the interior of said container beingnormally under pressure.

2. The method of operating an electrolyt-ic cell comprising a containerhaving an electrolyte therein having a chlorin anion which includes thestep of maintaining the interior of said container at a pressuresuficient to liquefy chlorin at the temperature of the container.

3. In an electric accumulator, the combination of a closed container, aporous vessel therein, a carbon rod packed with granular carbon withinthe vessel, metal gauze surrounding the vessel and a solutlon of analkaline chlorid and of the chlorid of an electropositive metal.

4:. In an electric accumulator, the combination of a closed container, aporous vessel therein, a carbon rod packed with granular carbon withinthe vessel, metal gauze surrounding the vessel and a solution of calciumchlorid and of zinc chlorid.

In an electric accumulator, the combination of a closed container, aporous vessel therein, a carbon rod packed with granular `calciumchlorid and of zinc lis hereinafter intended to be increaseadvantageously the` carbon within the vessel, metal gauze surroundingthe vessel and a solution of an alkaline chlorid and of the chlorid ofan electropositive metal under pressure.

6. In an electric accumulator, the combination of a closed container, aporous vessel therein, a carbon rod packed with granular carbonsurrounding the vessel and a solution of chlorid under pressure.

f7. In an electric accumulator, the combination of a closed container, alurality of porous vessels therein, a carlion rod packed with granularcarbon within each vessel, metal gauzesurrounding each vessel and asolution of an alkaline chlorid and of the chlorid of an electropositivemetal.

8. In an electric accumulator, the combination of a closed container, aplurality of porous vessels therein, a carbon rod packed with granularcarbon within each vessel, metal gauze surroundin each vessel and asolution of calcium 'ch orid and of zinc chlorid.

9. In an electric accumulator, the comblnatlon of a closed container, alurality `of porous vessels therein, a car on rod packed with granularcarbon within each vessel, metal gauze surrounding each vessel, asolution of an alkaline chlorid and of the chlorid of an electropositivemetal, and means whereby gas under pressure can be forced into thecontainer.

10. In an electric accumulator, the combination of a closed container, aplurality of porous vessels therein, a carbon rod packed with granularcarbon within each vessel, metal gauze surrounding each vessel, asolution of calcium chlorid and of zinc chlorid, and means whereby gasunder pressure can be forced into the container.

11. In an electric accumulator, the combination of a closed container, aplurality'of porous vessels therein, a carbon. rod packed with granularcarbon within eachvessel, metal gauze surrounding each vessel, asolution of an alkaline chlorid and of the chlorid of an electropositivemetal, means whereby gas under pressure can be forced into the containerand means for causing a circulation of the solution.

12. In an electric accumulator, the combination of a closed container, alurality ofr porous vessels therein, a carhon rod packed with granularcarbon within each vessel, metal gauze surrounding each vessel, asolution of calcium chlorid and of zinc chlorid, means whereby gas underpressure can be forced into the container, and means for causing acirculation of the solution.

13. In an electric accumulator, the combination of a closed container, aplurality of porous vessels therein, a carbon rod packed with granularcarbon within each vessel,

within the vessel, metal gauzemetal gauze surrounding each vessel, asolution of an alkaline chlorid and of the chlorid of an electropositivemetal, a circulating tube and means operated by the current from theaccumulator for heating the solution within such tube.

14. In an electric accumulator, the combination of a closed container, aplurality of crous vessels therein, a carbon rod packed with granularcarbon Within each Vessel, metal gauze surrounding each vessel, asolution of calcium chlorid and of zinc chlorid, a circulating tube andmeans operated by the current from the accumulator for heating thesolution Within such tube.

- 15. ln an electric accumulator, the combination of a closed container,a plurality of porous vessels therein, a carbon rod packed with granularcarbon Within each vessel, metal gauze surrounding each Vessel, asolution of an alkaline chlorid and of the 'chlorid of an'electropositive metal, means whereby gas under pressure can be forcedinto the container, a circulating tube and means operated by the currentfrom the accumulator for heating the solution Within such tube.

16. In an electric accumulator, the combination of a closed container, aplurality of porous vessels therein, a carbon rod packed with granularcarbon Within each vessel, metal gauze surrounding each Vessel, asolution of calcium chlorid and of zinc chlorid, means whereby gas underpressure can be forced into the container, a circulating tube and meansoperated by the current from the accumulator for heating the solutionWithin such tube.

In testimony as my invention, l have signed my name this fourteenth dagrof Februa 1918.

UGLELM MCON.

that l claim the foregoing"r

